Diethyl carbonate (sometimes abbreviated DEC) is a carbonate ester of carbonic acid and ethanol with the formula OC(OCH2CH3)2. At room temperature (25 °C) diethyl carbonate is a clear liquid with a low flash point.
Diethyl carbonate is used as a solvent such as in erythromycin intramuscular injections. It can be used as a component of electrolytes in lithium batteries. It has been proposed as a fuel additive to support cleaner diesel fuel combustion because its high boiling point might reduce blended fuels' volatility, minimize vapor buildup in warm weather that can block fuel lines.